Fuel Filter: Description and Operation

Figure 3-4: Fuel Filler Breakdown:

Fuel Filter-Water Separator

The filter-water separator is located at the driver side of the engine compartment firewall (Figure 3-4). It performs five functions which are:
- Fuel filtering (2-stage)
- Water separation
- Water detection
- Water drain
- Fuel heater

Fuel filtering and water separation is through a 2-stage, replaceable filter element. The filter second stage causes water to separate from the fuel in the form of droplets. These droplets are collected in a reservoir at the bottom of the filter element housing. Water is then drained off through a drain valve and hose. The drain valve is located in the driver side wheel well.

Water detection and fuel heating are controlled by sensors in the filter housing. Water build-up causes the water sensor to activate the instrument panel "drain filter" warning light. Fuel heating occurs during cold ambient temperatures. It is controlled by a sensor in the fuel inlet port that monitors incoming fuel temperature. When temperature falls to a point where wax build-up could occur, the sensor activates the heat element within the filter housing. The heater will continue to operate until incoming fuel temperature is at or above 46 °F (8 °C).